The role of low carbon and high carbon materials in carbon neutrality science and carbon economics

Focusing on switching the energy inputs to economies from fossil fuels to renewable energy and neglecting material outputs gives an overoptimistic picture of achieving carbon neutrality. We propose a set of equations that integrate analysis of energy and materials, provide a framework for a new carbon neutrality science, and lead to three carbon neutrality conditions. The equations are applied to low carbon materials, such as metals, and high carbon materials, such as wood. Refining carbon is the key carbon dioxide (CO2) emissions source to minimize for steel and aluminium, but slow technological change could leave a 'carbon neutrality gap' by 2050. This will be even greater unless forest expansion is accelerated to offset CO2 emissions. Principles of a new carbon economics are proposed and applied. Policy priorities include integrating energy and materials in carbon neutrality strategies, strengthening carbon reporting standards, establishing national wood products databases, increasing afforestation rates, and controlling deforestation. (C) 2021 Published by Elsevier B.V.